I refer to my published applications No. GB 2200299 and WO90/00430 which relate to techniques for sealing a balloon neck, and which also describe other conventional techniques to seal necks.
A problem with conventional techniques is that they usually involve additional parts being supplied with the balloon. For example, an adhesive-sealable balloon may include a plastics tube inserted into the open neck to enable the balloon to be inflated without interfering with the adhesive. A valve-sealable balloon necessarily includes a one-way valve fitted into the balloon neck. Such additional parts are undesirable because they add to the cost and complexity of manufacture. Also, in the case of valve-sealable balloons, it has been found that the valves from balloons used in large quantities at promotional or sporting events may be deposited in farmland once the balloons have deflated and decayed. The valves can easily be eaten by farm animals and cause internal injuries to the animals, or they can cause damage to farm machinery.
A further problem with valve-sealed balloons is that the valve adds significantly to the weight of the balloon, which reduces the balloons buoyancy. In the case of balloons filled with heliox, it has been found that a 30 cm (12 inch) size balloon is required in order to generate sufficient lift to rise when fitted with a conventional valve. Such a size of balloon requires 35% more gas for filling than would a more economical 25 cm (10 inch) size balloon, which is normally unable to rise when fitted with a valve.
Additionally, conventional techniques do not permit efficient automatic inflating and releasing of balloons on a large scale at a remote release site. Often, when a large balloon release is planned at, for example, an outdoor event, a hundred or more people will be required to inflate and seal the balloons manually. Such techniques are very time consuming and labour intensive, and this adds significantly to the cost of the balloon release.
The present invention has been devised with the above drawbacks in mind.